Privacy Policy

Dueloku is a real-time, head-to-head competitive sudoku game available on the web and as a mobile app. This Privacy Policy explains what information we collect when you use Dueloku (the "Service"), how we use and share it, and the choices and rights you have. By using the Service, you agree to the practices described here.

In this policy, "we", "us", and "Dueloku" refer to the operator of the Service. If you have any questions, contact us at privacy@dueloku.com.

Account information. When you create an account we collect your email address and a securely hashed version of your password (we never store your password in plain text). If you sign in with Google, we receive your Google account identifier and email address from Google. You may also play as a guest, in which case we create an anonymous account that holds no personal identifiers until you choose to convert it to a full account.

Profile information. A display name and, optionally, a profile image you choose to upload.

Gameplay information. Data generated as you play, including your ELO rating for each of the four difficulties, match history (results, rating changes, and timestamps), your friends list and head-to-head records, and leaderboard standings.

Information collected automatically. When you use the Service we automatically collect technical information through our analytics provider, including your IP address, device and browser type, pages and screens viewed, network requests and performance metrics, connection quality and latency, and similar diagnostic data. This helps us operate, secure, and improve the Service.

Cookies and local storage. We store authentication tokens and basic preferences in your browser or device storage so we can keep you signed in and remember your settings. We do not use third-party advertising cookies.

• Create and manage your account and authenticate you when you sign in.
• Match you with opponents, run live games, and maintain rankings, friends, and leaderboards.
• Operate, maintain, secure, and improve the Service, including diagnosing problems and analysing usage.
• Communicate with you about your account, such as email verification and important service notices.
• Detect, prevent, and respond to fraud, abuse, security incidents, and violations of our terms.
• Comply with legal obligations and enforce our rights.

If you are in the European Economic Area or the United Kingdom, we process your personal data on the following legal bases: to perform our contract with you (providing the Service and your account); our legitimate interests (securing and improving the Service, preventing abuse); your consent where required (for example, optional analytics where applicable); and to comply with legal obligations.

We do not sell your personal information, and we do not share it for cross-context behavioural advertising. We share information only with service providers who process it on our behalf and under contract:

• Google — for "Sign in with Google" authentication, when you choose to use it.
• Microsoft Azure — for cloud hosting, database storage, profile-image storage, and application analytics (Azure Application Insights).

We may also disclose information if required by law, to enforce our terms, or to protect the rights, safety, and security of our users and the Service. Other players can see limited public profile information you choose to share, such as your display name, profile image, ratings, and leaderboard position.

We keep your personal information for as long as your account is active or as needed to provide the Service. When you delete your account, we delete or anonymise your personal information within a reasonable period, except where we are required to retain certain data to comply with legal obligations, resolve disputes, or enforce our agreements. Aggregated or de-identified data that can no longer be linked to you may be retained.

Depending on where you live, you may have rights over your personal information, including the right to access, correct, delete, or export your data; to object to or restrict certain processing; and to withdraw consent. If you are a California resident, you have the right to know what personal information we collect, to request deletion, to correct inaccurate information, and not to be discriminated against for exercising your rights. To exercise any of these rights, contact us at privacy@dueloku.com. We will respond within the time required by applicable law.

You can request deletion of your account and associated personal data at any time:

• In the app or on the web: open your account settings and choose to delete your account, where available.
• By email: send a request from your account email address to privacy@dueloku.com with the subject "Delete my account". We will verify your request and delete your account.

When you delete your account we remove your personal information — including your email, profile, gameplay history, ratings, and friends — within 30 days, except for limited data we are legally required to retain. Guest (anonymous) accounts and their data are removed when the account is deleted or after a period of inactivity.

We use technical and organisational measures to protect your information, including encrypted connections (HTTPS), hashed passwords, and signed authentication tokens. No method of transmission or storage is completely secure, so we cannot guarantee absolute security, but we work to protect your data and to respond promptly to any incident.

Dueloku is not directed to children under 13 (or the minimum age required in your country), and we do not knowingly collect personal information from them. If you believe a child has provided us with personal information, contact us at privacy@dueloku.com and we will delete it.

We operate using cloud infrastructure that may process and store data in countries other than your own. Where we transfer personal data internationally, we rely on appropriate safeguards as required by applicable law.

We may update this Privacy Policy from time to time. When we make material changes, we will update the "Last updated" date above and, where appropriate, notify you through the Service. Your continued use of Dueloku after an update means you accept the revised policy.

If you have questions, concerns, or requests regarding this Privacy Policy or your personal information, contact us at privacy@dueloku.com.